I really don't know much about the XRTs, but I found this on Wikipedia:

The Precedent cart uses an aluminum box-tube style frame, which, with modifications, also underpins the line of XRT 4 wheel drive vehicles. The Precedent frame is extremely similar to the design of the DS, but does not use as much aluminum for it uses a composite panel that underpins the floorboard and parts of the engine or battery compartment. This member is friction-bonded to the rest of the carriage.

I guess I really just need someone to talk me out of spending 8k when I already have a perfectly good DS, albeit in all it's factory stock glory.

Ok here goes:

You can put a lift and bigger wheels/tires as well as an upgraded drive system on your DS for much less than $8k. A lift, wheels, tires, controller, cables, motor would probably be between $2-3k total, and you can customize it how you want...

The XRT850 and the XRT810 are both on a DS frame. The 850 has a factory Z-Bar lift kit. The 810 does not. Otherwise, pretty much the same car. The 810 uses a different rear body with a plastic dump bed. The 850 uses a DS rear body.